The 2013-14 Premier League season could be one of the most unpredictable to date with so many changes at the top.

This will be the first Premier League campaign without Sir Alex Ferguson in charge of Manchester United and there are at least four teams hoping to take advantage of David Moyes's inexperience of winning trophies.

Manchester City and Chelsea, both also under new management, and Tottenham have all spent big this summer, while Arsenal have kept hold of their key players and still have money to spend.

The spending is not restricted to this season's title contenders - Liverpool, Norwich, Southampton, Swansea and West Ham have all spent over £15m each this summer, as have Cardiff who, along with the other promoted sides Crystal Palace and Hull, will have to adjust to life back in England's top flight.

BBC Sport takes a look at what all 20 Premier League clubs have been up to over the summer and how they may get on this season.

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EXPERT'S VIEW: BBC WM's Mike Taylor: "Paul Lambert has added a group of largely unfamiliar players to his squad, and if he is as successful as he was with a similar tactic last summer, Villa fans will be happy enough.

"A top-10 finish would be excellent, but a season keeping away from trouble would be progress."

Aston Villa striker Christian Benteke: "The objective is to do better than last season. We have quality in the team. We have to try to do better. That's our aim.

"It was maybe a tough beginning last season but we finished well, so why not do something good this season?"

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EXPERT'S VIEW: BBC Radio Wales' Rob Phillips: "Survival is the target for the club backed by the Malaysian millions of Vincent Tan.

"The eye-catching capture of England defender Steven Caulker from Tottenham shows intent; Craig Bellamy's insatiable drive and experience will be a key factor and South Korea international Kim Bo Kyung looks top-flight material."

Cardiff boss Malky Mackay: "We fully understand how different this season is going to be. It's something I'm going to be very open with the fans [about] in terms of the backing they are going to have to give us at certain times of the season.

"It is going to be difficult. This season we're going to be playing against some real top teams and it's something that we've got to look at over the whole season."

EXPERT'S VIEW: BBC London 94.9's Andrew Rowley: "Chelsea enter the season in high spirits after the return of manager Jose Mourinho.

"He already has another squad capable of a title push. Many believe that Wayne Rooney could be the final piece in the jigsaw as Mourinho looks to end Chelsea's three-year wait for the title."

Chelsea boss Jose Mourinho: "I think this pre-season has been very good, in sports terms and in social terms.

"We have some very young boys, but young boys with good talent. We can look to a good future even though the present is very good. The kids give a balance to the squad but also security for the future."

EXPERT'S VIEW: BBC London 94.9's Jamie Reid: "Palace haven't made any marquee signings and you fear that it could be a tough season but manager Ian Holloway enjoyed his previous crack at the Premier League with Blackpool and learned a lot.

"Dwight Gayle should prove an astute signing. Anything other than relegation will represent a good season."

Crystal Palace boss Ian Holloway: "I know we've got a lot of building to do. I know what it's like to be a club that comes up late and we are not in the same echelons as the top half of this table.

"It's like starting a marathon and they are 20 miles away. Are we going to catch them? That's the target."

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EXPERT'S VIEW: BBC Radio Merseyside's Mike Hughes: "The winds of change have been blowing around Goodison Park. The signings of Kone, Alcaraz and Robles were widely expected, but the capture of Barcelona forward Gerard Deulofeu was not.

"There's an air of optimism at Everton, although that could change if Marouane Fellaini or Leighton Baines are sold."

Everton boss Roberto Martinez: "We should be fighting to one day be in the Champions League spots.

"We cannot expect that to be a target straight away. The only thing I want is that every fan at Everton can be proud of what we are trying to do."

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Liverpool do not have to wait long to face traditional rivals Manchester United, managed by ex-Everton boss David Moyes. They meet on 1 September, the third match day of the season, with the Old Trafford game on 15 March.

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EXPERT'S VIEW: BBC Radio Manchester's Bill Rice: "New manager David Moyes has inherited a title-winning squad full of quality and depth, and will hope to add his own signings before the transfer deadline.

"In his farewell speech, Sir Alex Ferguson asked the fans to give Moyes some time, but silverware is expected every season at Old Trafford."

Manchester United boss David Moyes: "I think we'd like to have a bit more continuity than we've had in pre-season.

"We've had one or two players dropping in and out because of injury but the players have been great and I look forward to the season starting."

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EXPERT'S VIEW: BBC Radio Norfolk's Chris Goreham: "It's been another summer of change with Grant Holt being sold. Big things are expected of record signing Ricky van Wolfswinkel. The rest of City's summer business looks shrewd.

"The Canaries will be hoping to build on solid finishes in their first two Premier League seasons since promotion."

Norwich boss Chris Hughton: "We've had two very good seasons in this division, but this season - irrespective of what we've brought in - will start just as hard as last season started.

"It's still making sure we start next season's Premier League in the division - that's always the objective - but we want to make progress."

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EXPERT'S VIEW: BBC Radio Solent's Adam Blackmore: "Saints have acquired two of their top targets in Dejan Lovren and Victor Wanyama, and look to have more backbone and defensive solidity.

"They are still searching for a top striker. If they add quality up front before the window shuts, then expect Saints to become a top-10 side."

Southampton midfielder Steven Davis: "Over the course of pre-season we've managed to test ourselves against different styles of play, against good opposition.

"Pre-season is all about building your fitness and getting ready for the first game of the season, so now we're getting that little bit closer everyone's getting a bit more excited. We've got a lot to look forward to this year and hopefully we can get off to a good start at West Brom."

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EXPERT'S VIEW: BBC Radio Stoke's Graham McGarry: "Many may see changing their manager as a risk, but a change of style from their notoriously direct approach will bring fresh optimism for the faithful Stoke fans.

"If goals can be added to a team that is usually hard to beat then it will be a good season for the Potters."

Stoke boss Mark Hughes: "It's not a case of wiping away all the hard work that's been put in place in previous seasons. That would be crazy.

"But I would like to think I can make them a bit more offensive and maybe that's where the club hasn't helped itself in the past - by not scoring enough goals."

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EXPERT'S VIEW: BBC Newcastle's Nick Barnes: "Signing so many players from abroad with no Premier League experience is risky.

"If they can adjust to the rigours of the English winter then Sunderland could enjoy a successful season. The manager's temperament will be under the spotlight but there's no doubt this season will be an adventure."

Sunderland goalkeeper Keiren Westwood: "There are a lot of new signings in the squad and we're evolving to the way the manager wants us to play.

"The lads who were here when he arrived last season know what he expects from us. Now it's up to the new players to get up to speed. They have done really well."

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EXPERT'S VIEW: BBC London 94.9's Nick Godwin: "A year ago Spurs were hoping to return to the Champions League and hang on to their biggest star. Twelve months later, not much has changed.

"You get the feeling that Andres Villas-Boas's risk-averse employers will have to gamble to take the club back into the top four."

Tottenham boss Andre Villas-Boas: "Our step at the moment is to be into the Champions League, probably not title contenders but we hope to be competitive next season if we manage to do things properly in the summer."

EXPERT'S VIEW: BBC London 94.9's Phil Parry: "The Hammers made a solid return to the top flight and it is difficult to see beyond the same for this year.

"A manager who prepares with precision, a squad with plenty of experience and a striker in the shape of Andy Carroll who will want to prove big points."

West Ham boss Sam Allardyce: "This has been one of the quietest summers I've had," he told talkSPORT.

"We have done some good business. Andy Carroll has come in, we've got a new goalkeeper in Adrian from Real Betis, who seems to be settling in very well, and Razvan Rat will help strengthen the defence."